1 /* gmain.h - the GLib Main loop
2 * Copyright (C) 1998-2000 Red Hat, Inc.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
20 #if defined(G_DISABLE_SINGLE_INCLUDES) && !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
21 #error "Only <glib.h> can be included directly."
27 #include <glib/gpoll.h>
28 #include <glib/gslist.h>
29 #include <glib/gthread.h>
36 * The <structname>GMainContext</structname> struct is an opaque data
37 * type representing a set of sources to be handled in a main loop.
39 typedef struct _GMainContext GMainContext;
44 * The <structname>GMainLoop</structname> struct is an opaque data type
45 * representing the main event loop of a GLib or GTK+ application.
47 typedef struct _GMainLoop GMainLoop;
52 * The <structname>GSource</structname> struct is an opaque data type
53 * representing an event source.
55 typedef struct _GSource GSource;
56 typedef struct _GSourcePrivate GSourcePrivate;
59 * GSourceCallbackFuncs:
60 * @ref: Called when a reference is added to the callback object
61 * @unref: Called when a reference to the callback object is dropped
62 * @get: Called to extract the callback function and data from the
65 * The <structname>GSourceCallbackFuncs</structname> struct contains
66 * functions for managing callback objects.
68 typedef struct _GSourceCallbackFuncs GSourceCallbackFuncs;
72 * @prepare: Called before all the file descriptors are polled. If the
73 * source can determine that it is ready here (without waiting for the
74 * results of the poll() call) it should return %TRUE. It can also return
75 * a @timeout_ value which should be the maximum timeout (in milliseconds)
76 * which should be passed to the poll() call. The actual timeout used will
77 * be -1 if all sources returned -1, or it will be the minimum of all the
78 * @timeout_ values returned which were >= 0.
79 * @check: Called after all the file descriptors are polled. The source
80 * should return %TRUE if it is ready to be dispatched. Note that some
81 * time may have passed since the previous prepare function was called,
82 * so the source should be checked again here.
83 * @dispatch: Called to dispatch the event source, after it has returned
84 * %TRUE in either its @prepare or its @check function. The @dispatch
85 * function is passed in a callback function and data. The callback
86 * function may be %NULL if the source was never connected to a callback
87 * using g_source_set_callback(). The @dispatch function should call the
88 * callback function with @user_data and whatever additional parameters
89 * are needed for this type of event source.
90 * @finalize: Called when the source is finalized.
94 * The <structname>GSourceFuncs</structname> struct contains a table of
95 * functions used to handle event sources in a generic manner.
97 * For idle sources, the prepare and check functions always return %TRUE
98 * to indicate that the source is always ready to be processed. The prepare
99 * function also returns a timeout value of 0 to ensure that the poll() call
100 * doesn't block (since that would be time wasted which could have been spent
101 * running the idle function).
103 * For timeout sources, the prepare and check functions both return %TRUE
104 * if the timeout interval has expired. The prepare function also returns
105 * a timeout value to ensure that the poll() call doesn't block too long
106 * and miss the next timeout.
108 * For file descriptor sources, the prepare function typically returns %FALSE,
109 * since it must wait until poll() has been called before it knows whether
110 * any events need to be processed. It sets the returned timeout to -1 to
111 * indicate that it doesn't mind how long the poll() call blocks. In the
112 * check function, it tests the results of the poll() call to see if the
113 * required condition has been met, and returns %TRUE if so.
115 typedef struct _GSourceFuncs GSourceFuncs;
120 * A type which is used to hold a process identification.
122 * On UNIX, processes are identified by a process id (an integer),
123 * while Windows uses process handles (which are pointers).
128 * @user_data: data passed to the function, set when the source was
129 * created with one of the above functions
131 * Specifies the type of function passed to g_timeout_add(),
132 * g_timeout_add_full(), g_idle_add(), and g_idle_add_full().
134 * Returns: %FALSE if the source should be removed
136 typedef gboolean (*GSourceFunc) (gpointer user_data);
140 * @pid: the process id of the child process
141 * @status: Status information about the child process,
142 * see waitpid(2) for more information about this field
143 * @user_data: user data passed to g_child_watch_add()
145 * The type of functions to be called when a child exists.
147 typedef void (*GChildWatchFunc) (GPid pid,
153 gpointer callback_data;
154 GSourceCallbackFuncs *callback_funcs;
156 GSourceFuncs *source_funcs;
159 GMainContext *context;
172 GSourcePrivate *priv;
175 struct _GSourceCallbackFuncs
177 void (*ref) (gpointer cb_data);
178 void (*unref) (gpointer cb_data);
179 void (*get) (gpointer cb_data,
186 * GSourceDummyMarshal:
188 * This is just a placeholder for #GClosureMarshal,
189 * which cannot be used here for dependency reasons.
191 typedef void (*GSourceDummyMarshal) (void);
195 gboolean (*prepare) (GSource *source,
197 gboolean (*check) (GSource *source);
198 gboolean (*dispatch) (GSource *source,
199 GSourceFunc callback,
201 void (*finalize) (GSource *source); /* Can be NULL */
203 /* For use by g_source_set_closure */
204 GSourceFunc closure_callback;
205 GSourceDummyMarshal closure_marshal; /* Really is of type GClosureMarshal */
208 /* Standard priorities */
213 * Use this for high priority event sources.
215 * It is not used within GLib or GTK+.
217 #define G_PRIORITY_HIGH -100
220 * G_PRIORITY_DEFAULT:
222 * Use this for default priority event sources.
224 * In GLib this priority is used when adding timeout functions
225 * with g_timeout_add(). In GDK this priority is used for events
228 #define G_PRIORITY_DEFAULT 0
231 * G_PRIORITY_HIGH_IDLE:
233 * Use this for high priority idle functions.
235 * GTK+ uses #G_PRIORITY_HIGH_IDLE + 10 for resizing operations,
236 * and #G_PRIORITY_HIGH_IDLE + 20 for redrawing operations. (This is
237 * done to ensure that any pending resizes are processed before any
238 * pending redraws, so that widgets are not redrawn twice unnecessarily.)
240 #define G_PRIORITY_HIGH_IDLE 100
243 * G_PRIORITY_DEFAULT_IDLE:
245 * Use this for default priority idle functions.
247 * In GLib this priority is used when adding idle functions with
250 #define G_PRIORITY_DEFAULT_IDLE 200
255 * Use this for very low priority background tasks.
257 * It is not used within GLib or GTK+.
259 #define G_PRIORITY_LOW 300
264 * Use this macro as the return value of a #GSourceFunc to remove
265 * the #GSource from the main loop.
269 #define G_SOURCE_REMOVE FALSE
274 * Use this macro as the return value of a #GSourceFunc to leave
275 * the #GSource in the main loop.
279 #define G_SOURCE_CONTINUE TRUE
283 GMainContext *g_main_context_new (void);
284 GMainContext *g_main_context_ref (GMainContext *context);
285 void g_main_context_unref (GMainContext *context);
286 GMainContext *g_main_context_default (void);
288 gboolean g_main_context_iteration (GMainContext *context,
290 gboolean g_main_context_pending (GMainContext *context);
292 /* For implementation of legacy interfaces
294 GSource *g_main_context_find_source_by_id (GMainContext *context,
296 GSource *g_main_context_find_source_by_user_data (GMainContext *context,
298 GSource *g_main_context_find_source_by_funcs_user_data (GMainContext *context,
302 /* Low level functions for implementing custom main loops.
304 void g_main_context_wakeup (GMainContext *context);
305 gboolean g_main_context_acquire (GMainContext *context);
306 void g_main_context_release (GMainContext *context);
307 gboolean g_main_context_is_owner (GMainContext *context);
308 gboolean g_main_context_wait (GMainContext *context,
312 gboolean g_main_context_prepare (GMainContext *context,
314 gint g_main_context_query (GMainContext *context,
319 gint g_main_context_check (GMainContext *context,
323 void g_main_context_dispatch (GMainContext *context);
325 void g_main_context_set_poll_func (GMainContext *context,
327 GPollFunc g_main_context_get_poll_func (GMainContext *context);
329 /* Low level functions for use by source implementations
331 void g_main_context_add_poll (GMainContext *context,
334 void g_main_context_remove_poll (GMainContext *context,
337 gint g_main_depth (void);
338 GSource *g_main_current_source (void);
340 /* GMainContexts for other threads
342 void g_main_context_push_thread_default (GMainContext *context);
343 void g_main_context_pop_thread_default (GMainContext *context);
344 GMainContext *g_main_context_get_thread_default (void);
345 GMainContext *g_main_context_ref_thread_default (void);
349 GMainLoop *g_main_loop_new (GMainContext *context,
350 gboolean is_running);
351 void g_main_loop_run (GMainLoop *loop);
352 void g_main_loop_quit (GMainLoop *loop);
353 GMainLoop *g_main_loop_ref (GMainLoop *loop);
354 void g_main_loop_unref (GMainLoop *loop);
355 gboolean g_main_loop_is_running (GMainLoop *loop);
356 GMainContext *g_main_loop_get_context (GMainLoop *loop);
360 GSource *g_source_new (GSourceFuncs *source_funcs,
362 GSource *g_source_ref (GSource *source);
363 void g_source_unref (GSource *source);
365 guint g_source_attach (GSource *source,
366 GMainContext *context);
367 void g_source_destroy (GSource *source);
369 void g_source_set_priority (GSource *source,
371 gint g_source_get_priority (GSource *source);
372 void g_source_set_can_recurse (GSource *source,
373 gboolean can_recurse);
374 gboolean g_source_get_can_recurse (GSource *source);
375 guint g_source_get_id (GSource *source);
377 GMainContext *g_source_get_context (GSource *source);
379 void g_source_set_callback (GSource *source,
382 GDestroyNotify notify);
384 void g_source_set_funcs (GSource *source,
385 GSourceFuncs *funcs);
386 gboolean g_source_is_destroyed (GSource *source);
388 void g_source_set_name (GSource *source,
390 const char * g_source_get_name (GSource *source);
391 void g_source_set_name_by_id (guint tag,
395 /* Used to implement g_source_connect_closure and internally*/
396 void g_source_set_callback_indirect (GSource *source,
397 gpointer callback_data,
398 GSourceCallbackFuncs *callback_funcs);
400 void g_source_add_poll (GSource *source,
402 void g_source_remove_poll (GSource *source,
405 void g_source_add_child_source (GSource *source,
406 GSource *child_source);
407 void g_source_remove_child_source (GSource *source,
408 GSource *child_source);
410 #ifndef G_DISABLE_DEPRECATED
411 void g_source_get_current_time (GSource *source,
412 GTimeVal *timeval) G_GNUC_DEPRECATED_FOR(g_source_get_time);
414 gint64 g_source_get_time (GSource *source);
416 /* void g_source_connect_closure (GSource *source,
420 /* Specific source types
422 GSource *g_idle_source_new (void);
423 GSource *g_child_watch_source_new (GPid pid);
424 GSource *g_timeout_source_new (guint interval);
425 GSource *g_timeout_source_new_seconds (guint interval);
427 /* Miscellaneous functions
429 void g_get_current_time (GTimeVal *result);
430 gint64 g_get_monotonic_time (void);
431 gint64 g_get_real_time (void);
433 /* ============== Compat main loop stuff ================== */
435 #ifndef G_DISABLE_DEPRECATED
439 * @is_running: set to %TRUE to indicate that the loop is running. This
440 * is not very important since calling g_main_run() will set this
443 * Creates a new #GMainLoop for th default main context.
445 * Returns: a new #GMainLoop
447 * Deprecated: 2.2: Use g_main_loop_new() instead
449 #define g_main_new(is_running) g_main_loop_new (NULL, is_running)
453 * @loop: a #GMainLoop
455 * Runs a main loop until it stops running.
457 * Deprecated: 2.2: Use g_main_loop_run() instead
459 #define g_main_run(loop) g_main_loop_run(loop)
463 * @loop: a #GMainLoop
465 * Stops the #GMainLoop.
466 * If g_main_run() was called to run the #GMainLoop, it will now return.
468 * Deprecated: 2.2: Use g_main_loop_quit() instead
470 #define g_main_quit(loop) g_main_loop_quit(loop)
474 * @loop: a #GMainLoop
476 * Frees the memory allocated for the #GMainLoop.
478 * Deprecated: 2.2: Use g_main_loop_unref() instead
480 #define g_main_destroy(loop) g_main_loop_unref(loop)
484 * @loop: a #GMainLoop
486 * Checks if the main loop is running.
488 * Returns: %TRUE if the main loop is running
490 * Deprecated: 2.2: Use g_main_loop_is_running() instead
492 #define g_main_is_running(loop) g_main_loop_is_running(loop)
496 * @may_block: set to %TRUE if it should block (i.e. wait) until an event
497 * source becomes ready. It will return after an event source has been
498 * processed. If set to %FALSE it will return immediately if no event
499 * source is ready to be processed.
501 * Runs a single iteration for the default #GMainContext.
503 * Returns: %TRUE if more events are pending.
505 * Deprecated: 2.2: Use g_main_context_iteration() instead.
507 #define g_main_iteration(may_block) g_main_context_iteration (NULL, may_block)
512 * Checks if any events are pending for the default #GMainContext
513 * (i.e. ready to be processed).
515 * Returns: %TRUE if any events are pending.
517 * Deprected: 2.2: Use g_main_context_pending() instead.
519 #define g_main_pending() g_main_context_pending (NULL)
522 * g_main_set_poll_func:
523 * @func: the function to call to poll all file descriptors
525 * Sets the function to use for the handle polling of file descriptors
526 * for the default main context.
528 * Deprecated: 2.2: Use g_main_context_set_poll_func() again
530 #define g_main_set_poll_func(func) g_main_context_set_poll_func (NULL, func)
532 #endif /* G_DISABLE_DEPRECATED */
534 /* Source manipulation by ID */
535 gboolean g_source_remove (guint tag);
536 gboolean g_source_remove_by_user_data (gpointer user_data);
537 gboolean g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
540 /* Idles, child watchers and timeouts */
541 guint g_timeout_add_full (gint priority,
543 GSourceFunc function,
545 GDestroyNotify notify);
546 guint g_timeout_add (guint interval,
547 GSourceFunc function,
549 guint g_timeout_add_seconds_full (gint priority,
551 GSourceFunc function,
553 GDestroyNotify notify);
554 guint g_timeout_add_seconds (guint interval,
555 GSourceFunc function,
557 guint g_child_watch_add_full (gint priority,
559 GChildWatchFunc function,
561 GDestroyNotify notify);
562 guint g_child_watch_add (GPid pid,
563 GChildWatchFunc function,
565 guint g_idle_add (GSourceFunc function,
567 guint g_idle_add_full (gint priority,
568 GSourceFunc function,
570 GDestroyNotify notify);
571 gboolean g_idle_remove_by_data (gpointer data);
573 void g_main_context_invoke_full (GMainContext *context,
575 GSourceFunc function,
577 GDestroyNotify notify);
578 void g_main_context_invoke (GMainContext *context,
579 GSourceFunc function,
582 /* Hook for GClosure / GSource integration. Don't touch */
583 GLIB_VAR GSourceFuncs g_timeout_funcs;
584 GLIB_VAR GSourceFuncs g_child_watch_funcs;
585 GLIB_VAR GSourceFuncs g_idle_funcs;
589 #endif /* __G_MAIN_H__ */